CLDR-17314 String.intern() across multiple locations

- Unit test to verify that CLDRFile paths are interned
- interning in XPathTable and StringId

tools/cldr-apps/src/main/java/org/unicode/cldr/web/XPathTable.java

@@ -269,6 +269,7 @@ private synchronized void addXpaths(Set<String> xpaths, Connection conn) throws
      * @return the xpath's id (as an Integer)
      */
     private synchronized Integer addXpath(String xpath, boolean addIfNotFound, Connection inConn) {
+        xpath = xpath.intern();
         Integer nid = stringToId.get(xpath); // double check
         if (nid != null) {
             return nid;
@@ -372,6 +373,7 @@ public final String getById(int id) {
      *     //ldml/dates/timeZoneNames/zone[@type="America/Guadeloupe"]/short/daylight
      */
     public final void setById(int id, String xpath) {
+        xpath = xpath.intern();
         stringToId.put(idToString_put(id, xpath), id);
         sidToString.put(getStringID(xpath), xpath);
     }
@@ -383,6 +385,7 @@ public final void setById(int id, String xpath) {
      * @return the id, like 692804, for the specified path
      */
     public final int getByXpath(String xpath) {
+        xpath = xpath.intern();
         Integer nid = stringToId.get(xpath);
         if (nid != null) {
             return nid.intValue();

tools/cldr-code/src/main/java/org/unicode/cldr/util/CLDRFile.java

@@ -3156,8 +3156,8 @@ public Set<String> getRawExtraPaths() {
         if (extraPaths == null) {
             extraPaths =
                     ImmutableSet.<String>builder()
-                            .addAll(getRawExtraPathsPrivate())
-                            .addAll(CONST_EXTRA_PATHS)
+                            .addAll(CharUtilities.internAll(getRawExtraPathsPrivate()))
+                            .addAll(CharUtilities.internAll(CONST_EXTRA_PATHS))
                             .build();
             if (DEBUG) {
                 System.out.println(getLocaleID() + "\textras: " + extraPaths.size());

tools/cldr-code/src/main/java/org/unicode/cldr/util/CharUtilities.java

@@ -1,7 +1,31 @@
 package org.unicode.cldr.util;
 
+import java.util.Iterator;
+
 public class CharUtilities {
+    /** intern everything in the src iterable */
+    public static Iterable<String> internAll(final Iterable<String> src) {
+        return new Iterable<String>() {
+            @Override
+            public Iterator<String> iterator() {
+                return CharUtilities.internAll(src.iterator());
+            }
+        };
+    }
+    /** intern everything in the src iterator */
+    protected static Iterator<String> internAll(final Iterator<String> iterator) {
+        return new Iterator<String>() {
+            @Override
+            public boolean hasNext() {
+                return iterator.hasNext();
+            }
 
+            @Override
+            public String next() {
+                return iterator.next().intern();
+            }
+        };
+    }
     /**
      * Simple wrapper for CharSequence
      *

tools/cldr-code/src/main/java/org/unicode/cldr/util/SimpleXMLSource.java

@@ -108,11 +108,12 @@ public XMLSource cloneAsThawed() {
 
     @Override
     public void putFullPathAtDPath(String distinguishingXPath, String fullxpath) {
-        xpath_fullXPath.put(distinguishingXPath, fullxpath);
+        xpath_fullXPath.put(distinguishingXPath.intern(), fullxpath.intern());
     }
 
     @Override
     public void putValueAtDPath(String distinguishingXPath, String value) {
+        distinguishingXPath = distinguishingXPath.intern();
         String oldValue = xpath_value.get(distinguishingXPath);
         xpath_value.put(distinguishingXPath, value);
         updateValuePathMapping(distinguishingXPath, oldValue, value);

tools/cldr-code/src/main/java/org/unicode/cldr/util/StringId.java

@@ -34,7 +34,7 @@ public final class StringId {
      * @return a value from 0 to 0x7FFFFFFFFFFFFFFFL.
      */
     public static long getId(CharSequence charSequence) {
-        String string = charSequence.toString();
+        String string = charSequence.toString().intern();
         Long resultLong = STRING_TO_ID.get(string);
         if (resultLong != null) {
             return resultLong;

tools/cldr-code/src/main/java/org/unicode/cldr/util/XMLSource.java

@@ -261,6 +261,7 @@ public boolean isFrozen() {
      * @param value
      */
     public String putValueAtPath(String xpath, String value) {
+        xpath = xpath.intern();
         if (locked) {
             throw new UnsupportedOperationException("Attempt to modify locked object");
         }
@@ -493,7 +494,8 @@ private TreeMap<String, String> loadAliases() {
             if (!Alias.isAliasPath(path)) {
                 continue;
             }
-            String fullPath = getFullPathAtDPath(path);
+            path = path.intern();
+            String fullPath = getFullPathAtDPath(path).intern();
             Alias temp = Alias.make(fullPath);
             if (temp == null) {
                 continue;
@@ -892,6 +894,7 @@ public Date getChangeDateAtDPath(String xpath) {
         private String getFullPath(
                 String xpath, AliasLocation fullStatus, String fullPathWhereFound) {
             String result = null;
+            xpath = xpath.intern();
             if (this.cachingIsEnabled) {
                 result = getFullPathAtDPathCache.get(xpath);
             }
@@ -1078,6 +1081,7 @@ private AliasLocation getPathLocation(
                 boolean skipFirst,
                 boolean skipInheritanceMarker,
                 List<LocaleInheritanceInfo> list) {
+            xpath = xpath.intern();
 
             //   When calculating the Bailey values, we track the final
             //   return value as firstValue. If non-null, this will become
@@ -1145,6 +1149,7 @@ private AliasLocation getPathLocation(
                     aliasedPath =
                             aliases.get(possibleSubpath)
                                     + xpath.substring(possibleSubpath.length());
+                    aliasedPath = aliasedPath.intern();
                     if (list != null) {
                         // It's an explicit alias, just at a parent element (subset xpath)
                         list.add(
@@ -1165,7 +1170,7 @@ private AliasLocation getPathLocation(
 
             // alts are special; they act like there is a root alias to the path without the alt.
             if (aliasedPath == null && xpath.contains("[@alt=")) {
-                aliasedPath = XPathParts.getPathWithoutAlt(xpath);
+                aliasedPath = XPathParts.getPathWithoutAlt(xpath).intern();
                 if (list != null) {
                     list.add(
                             new LocaleInheritanceInfo(
@@ -1178,10 +1183,10 @@ private AliasLocation getPathLocation(
             // //ldml/numbers/currencies/currency[@type="BRZ"]/displayName[@count="other"] =>
             // //ldml/numbers/currencies/currency[@type="BRZ"]/displayName
             if (aliasedPath == null && xpath.contains("[@count=")) {
-                aliasedPath = COUNT_EQUALS.matcher(xpath).replaceAll("[@count=\"other\"]");
+                aliasedPath = COUNT_EQUALS.matcher(xpath).replaceAll("[@count=\"other\"]").intern();
                 if (aliasedPath.equals(xpath)) {
                     if (xpath.contains("/displayName")) {
-                        aliasedPath = COUNT_EQUALS.matcher(xpath).replaceAll("");
+                        aliasedPath = COUNT_EQUALS.matcher(xpath).replaceAll("").intern();
                         if (aliasedPath.equals(xpath)) {
                             throw new RuntimeException("Internal error");
                         }
@@ -1290,7 +1295,7 @@ private Set<String> findNonAliasedPaths() {
             // others
             for (XMLSource curSource : sourceList) {
                 for (String xpath : curSource) {
-                    paths.add(xpath);
+                    paths.add(xpath.intern());
                 }
             }
             return paths;
@@ -1328,7 +1333,7 @@ private Set<String> getDirectAliases(String[] paths) {
                     String suffix = xpath.substring(suffixStart);
                     for (String reverseAlias : list) {
                         String reversePath = reverseAlias + suffix;
-                        newPaths.add(reversePath);
+                        newPaths.add(reversePath.intern());
                     }
                     endIndex++;
                 }
@@ -1967,7 +1972,7 @@ public XMLSource add(String currentFullXPath, String value) {
                 LOG_PROGRESS,
                 "ADDING: \t" + currentFullXPath + " \t" + value + "\t" + currentFullXPath);
         try {
-            this.putValueAtPath(currentFullXPath, value);
+            this.putValueAtPath(currentFullXPath.intern(), value);
         } catch (RuntimeException e) {
             throw new IllegalArgumentException(
                     "failed adding " + currentFullXPath + ",\t" + value, e);

tools/cldr-code/src/test/java/org/unicode/cldr/util/TestCLDRFile.java

@@ -352,4 +352,24 @@ public void testGetPaths() {
                                     .getPathsWhereFound(GERMAN_IN_SWITZERLAND));
         }
     }
+
+    @Test
+    public void TestInternedPaths() {
+        {
+            final CLDRFile en = CLDRConfig.getInstance().getCLDRFile("en", false);
+            for (final String s : en.fullIterable()) {
+                final String s0 = new String(s);
+                assertTrue(s != s0);
+                assertTrue(s == s0.intern(), () -> "in unresolved en was not interned: " + s);
+            }
+        }
+        {
+            final CLDRFile en = CLDRConfig.getInstance().getCLDRFile("en", true);
+            for (final String s : en.fullIterable()) {
+                final String s0 = new String(s);
+                assertTrue(s != s0);
+                assertTrue(s == s0.intern(), () -> "in resolved en was not interned: " + s);
+            }
+        }
+    }
 }